Questions tagged [blockchain]

The blockchain is the journal of all confirmed Bitcoin transactions. It consists of a linked sequence of blocks and each block contains a list of transactions. For questions about the eponymous company or its products please use [blockchain.info]!

Filter by
Sorted by
Tagged with
0 votes
2 answers
24 views

Deleting data in blockchain

I have read that block in blockchain is immutable since the next block is storing the hash of previous block . What if , to remove a block from the blockchain , I set the "previous hash" of ...
  • 1
1 vote
0 answers
25 views

Bitcoin Inscription Ordinals Store Sourcecode [closed]

Is there a use case to publish source code of any kind into the Bitcoin Blockchain using Ordinals?
-1 votes
1 answer
44 views

My multibit core synchronization is stuck Whats the reason [duplicate]

For the past six days since I downloaded the multibit core, I wanted to recover my wallet I still have my recovery phrase and password, and open the multibit core and the wallet was synchronization ...
2 votes
0 answers
87 views

The One Thing That’s Stopping Me From Accessing My Crypto Wallet (Hint: It’s Not the Seed Phrase)

Requirement: Recover crypto What I possess: I have a 12 word seed phrase, (Though I am not exactly sure of the organization that generated it). I have the public address through which (blockchain.com ...
-1 votes
0 answers
20 views

What tools are useful for Bitcoin Forensic?

Best wishes of health to all. After receiving several clients seeking advice, we need to equip ourselves with some tools that allow us to make simple reports on blockchain forensic, especially on ...
4 votes
1 answer
40 views

Size of the `chainstate/` dir vary from node to node

I run 2 nodes: a non-pruned, txindex=1 node that has been running for years (I can't tell exactly but I think I have been moving the same datadir around since 2014/15), core v23.0.0 a pruned node ...
  • 593
-2 votes
1 answer
58 views

How did Satoshi Nakamoto create the first Bitcoin? The Genesis Block

How did Satoshi Nakamoto create the first Bitcoin? I have never read any statement where he recommends specific tools like CGMiner. You can't mine with the Bitcoin Core software. Actually, Bitcoin ...
-1 votes
1 answer
61 views

I was recently contacted by blockchain, saying I have money in wallet,account is frozen ,and can recover money. Is this legit? Can't remember wallet

I was recently contacted by blockchain Acces UK claiming that I had created a bitcoin wallet years ago. Was informed wallet has 4.2 BTC coins in it which is equivalent to almost $40,000. The account ...
  • 1
5 votes
1 answer
381 views

Can I delete blk*.dat files?

Since bitcoin validates blockchain by the hash of older blocks recursively; Can I just keep the last blk*.dat file and delete the rest while the bitcoin core is downloading and validating the ...
  • 65
0 votes
0 answers
86 views

Why do many of the early bitcoin addresses receive small transactions many years later? [duplicate]

For example... https://www.blockchain.com/explorer/addresses/btc/1NHHWnZKTetjZZfAbVjTS9EHQafdH6xn8a ...receives a block reward of 50 BTC in 2009 and then transactions in 2019, 2020, 2021 for tiny ...
  • 275
1 vote
1 answer
33 views

Is it possible to add custom data on blockchains transaction such as a payment reference?

As we traditional bank it is possible to add a reference when sending money away. Is it possible to put some short custom data when sending a blockchain transaction, such as payment reference ? I'm ...
3 votes
2 answers
205 views

Downgrading Bitcoin Core 24.99 (latest source code) to 24.0.1

I wanted to build Bitcoin Core myself, so I followed this official guide, but in the process I failed to realize that by cloning the git repo I would just get the latest source code, not the latest ...
  • 31
3 votes
2 answers
929 views

Understanding how ordinals work with the Bitcoin blockchain. What is exactly stored on the blockchain?

Supposedly someone uploaded a Doom clone to the bitcoin blockchain: https://ordinals.com/content/521f8eccffa4c41a3a7728dd012ea5a4a02feed81f41159231251ecf1e5c79dai0 But I'm a bit confused on exactly ...
-3 votes
1 answer
2k views

Is bitcoin bonus and cloud mining real? [duplicate]

I received an email saying I have so much money from a cloud mining app that I set up using my phone and the app connected with my IP address.. I didn't really pay to much attention to the app so I ...
11 votes
1 answer
556 views

Follow-up to Segwit: Arbitrary data storage in witness?

In 2017 a question about Segwit: Arbitrary data storage in witness? asked whether people wanting to store more data in the blockchain than OP_RETURN allows could instead store data in the witness ...
0 votes
3 answers
54 views

What is the use of longest chain consensus rule?

I want to know Couldnt a chain be hardcoded in the bitcoin rules itself? Only so and so chain can be used. During the early days of bitcoin, I know a small group of enthusiasts were miners. And they ...
0 votes
0 answers
1k views

Has anybody ever got email in their doc saying they have funds from BTC Bitcoin bonus giveaway [duplicate]

So I got an email from in my docs saying that I had to go to this page and I had all mining earnimgs everything that I hadn't withdrawed from a year ago on on a platform I let them use my IP to mine ...
0 votes
0 answers
129 views

Google forms email [duplicate]

I got an email saying my account would be deleted soon and I earned a lot of Bitcoin I can't seem to figure out how to receive my money though It's from Bitcoin bonus A cloud mining platform is all I ...
0 votes
0 answers
29 views

NameError at /register name 'privtopub' is not defined

from django.shortcuts import render, redirect from django.contrib.auth.models import User, auth from django.contrib import messages from .models import Details from bitcoin import * import random ...
0 votes
0 answers
48 views

Error validating transaction: Error running script for input 0 referencing <vin-txid> at 0: Script was NOT

While broadcasting this multisig-segwit transaction on bitcoin testnet, I am getting this error Error validating transaction: Error running script for input 0 referencing ...
0 votes
1 answer
83 views

Why criminals still use bitcoin mixers when there is other blockchains?

I came across the following article Allen Goldmann, A person is trying to hide $5 million in stolen Bitcoins from a Darknet marketplace, Forbes, November 28, 2022 where some criminal tried to ...
  • 101
1 vote
2 answers
78 views

How many digital signatures appear in a block?

I am wondering how many times ECDSA digital signature are used across transactions in one block. Let's take for example Block #735,273. It contains 405 transactions. My understanding is that each ...
  • 13
0 votes
1 answer
65 views

Withdrew Bitcoin from Binance to someone's wallet. They said they never received it [duplicate]

I sent 0.3061 BTC from Binance 4 days ago to a wallet but the recipient said they never got anything. The address is bc1qsx2w6u4vgwmadp964s66yu6nuu85cdg58a9kpf. Every blockchain site says the ...
0 votes
1 answer
43 views

How is the Prev_block_id managed?

I found this schema. I wonder how organize the relationship with prev_block_id(prev_hash)? I think it would be like a below schema.(Here limited to id(hash)) CREATE TABLE block ( id VARCHAR(8) ...
1 vote
2 answers
104 views

Analyse huge amount of blockchain data

I am trying to go over all transactions data from every block on the bitcoin blockchain from the previous 4 years. With almost 2k transaction per block, it will take a lot of queries per block. I have ...
  • 11
0 votes
0 answers
46 views

Optimal way to design BTC withdraw flow?

I am designing an exchange application that allows users to deposit and withdraw BTC. During the withdraw process, several failures could happen (e.g. transaction gets stuck, transaction gets dropped ...
1 vote
0 answers
27 views

How can I obtain relayed_by IP via Blockchain Data API?

I have tried to look for "relayed_by" IP address via the Blockchain Data API for a few transactions but it always returns "relayed_by":"0.0.0.0". For example, https://...
2 votes
3 answers
70 views

How can I determine the block height on a certain day?

Is there an easy calculator to determine the block height on a certain day? i.e what was the block height on 14th October? This was asked by JoeNakamoto on Twitter. There is a related question on ...
0 votes
2 answers
102 views

Create a BTC account programmatically

Is that possible to create new BTC(or any other cryptocurrency) account through free api or kind of?
0 votes
2 answers
116 views

Blockchain's previous snapshot

Is there any way to download past btc transactions without running a full node? Searching about this, usually all the answers suggest to run a full node. I.e. I want a file that contains, say, all the ...
  • 101
1 vote
0 answers
33 views

latest UTXO databases received

There are many repositories that allow you to turn blockchain into UTXO. But I can't find where I could download ready-made UTXOs. I only find instructions on how to get such a database myself. ...
0 votes
0 answers
22 views

How to check the amount of currency in the wallets unlimited and without downloading the entire database?

I need to know by address how many coins at the moment and how many transactions (whether there were any transactions on the wallet at all). At the moment the base weighs 400gb. 100% option is to ...
1 vote
1 answer
55 views

Why is number of downloaded block files far fewer than current block height?

I'm attempting to download the entire blockchain and then run some analysis of wealth distribution at various points in time and in response to specific events. A website like blockchain.com's block ...
0 votes
1 answer
57 views

How to Generate P2SH Address from XPUB Ledger

I'm trying to Generate unused receiving Addresses for a Segwit P2SH wallet in my Ledger. I tried https://pypi.org/project/bitcoinlib/ but without success, the addresses weren't right. This is from my ...
-1 votes
2 answers
61 views

how can I launch my blockchain through bitcoin-core?

How can you run your blockchain, not through regtest, but a real one
0 votes
0 answers
74 views

How can I use blockchain.info websocket to constantly check for payments inside express API then update database

I'm trying to constantly check for a bunch of address's to see if they have been paid or not in real-time using websockets. I made a little express API that pulls the wallet from the database and then ...
0 votes
1 answer
45 views

Exploiting the use of signature?

I've just learned signatures and why they're used in blockchain. As I understand there is a key pair that consist of one public key and one private key: Private keys are used to sign a message(...
0 votes
1 answer
66 views

How are newly generated key-pairs kept unique to a single cryptocurrency?

As an extension to this question and some quick searches on software crypto wallets - my understanding is that any newly generated key-pair is unique to a specific cryptocurrency. Assuming this is ...
  • 15
-1 votes
1 answer
42 views

are the hubs on the internet the only hackable 'computer'?

Context here: I'm a newbie on internet&blockchain, but I read some article and they said on the internet, computers are connected through hub(s). So, It seems to me that there's no other 'users' ...
2 votes
3 answers
68 views

Relation between PoW and integrity?

I'm pretty new to the Blockchain technology. In a video that I watched, the lecturer talked about Consensus Algorithms and said that they're used for maintaining the integrity of the blockchain.  Then ...
1 vote
1 answer
48 views

Wrong hashes for blocks when parsing from blk

Hello I'm using a python script to actually retrieve information from a blk file and to read data. import datetime # Read block ! file = open("REDACTED\blocks\\blk00000.dat", 'rb') ...
1 vote
1 answer
65 views

Why is Bitcoin core deleting my blk files while downloading blockchain?

I want to download the bitcoin blockchain to actually be able to parse it using the blk files, but as I'm seeing right now while installing, bitcoin core is deleting them and keeps downloading newer ...
-1 votes
1 answer
90 views

Could you clarify the definition of bitcoin, that is "coin", which Nakamoto defined as "a chain of digital signatures"(details below)?

Say Alice buys 1 BTC and Bob 100 BTC. Nakamoto defined coin(BTC) as a "chain of digital signatures", so Alice bought 1 such chain, and Bob 100 chains. That makes no sense to me, so could you ...
  • 1
0 votes
0 answers
41 views

Double spending: Do miners generally adhere to the RBF-Flag (replace by fee) in on-chain transactions and the FSS-rule (First Seen Save)?

I've been reading some articles about 0-conf scams happening, where someone accepts bitcoin on-chain without waiting for even a single on-chain confirmation. In this blog post, it is described that ...
  • 1
2 votes
1 answer
120 views

How can I take a "snapshot" of the bitcoin blockchain and analyze it?

What I want to do: Download the copy of bitcoin blockchain Select from it all those addresses that have bitcoins (> 0.05 BTC) and they have not been active for > 7 days Display statistics on ...
2 votes
1 answer
94 views

What prevents miners from removing transactions when validating a node? [duplicate]

Simple question: when a miners receives a block of transactions, he can't add fraudulent transactions because they need to be appropriately signed, but what prevents him from erasing a tx? If he ...
0 votes
0 answers
15 views

BLOCKCHAIN CIRCULATOIN IF COIN NOT RECEIVE? [duplicate]

UK Company send some bitcoin in my wallet address but after 100 of confirmation bitcoin not showing in my Binance Account. So Depositer saying that recipient have to send half of actual value of ...
1 vote
1 answer
58 views

Restarting the bitcoin chain in a land far away, after a global total collapse disaster

So I've been thinking about this scenario, you are a survivor of a global disaster. Years later you find a running solar powered bitcoin node and want to restart the chain. You have a few running ...
  • 11
1 vote
0 answers
38 views

BlockCypher API signature bitcoin transaction Error

I'm trying to make a bitcoin transaction using the BlockCypher API and I'm getting an error when I try to sign the transaction. This function creates an unsigned transaction: def buildTransaction(...
1 vote
0 answers
133 views

Error `settings.json file has no read or write access` - but permissions OK

I was downloading the whole Bitcoin blockchain and the download stopped and I got an error message that the settings.json file has no read or write access, but I checked the permissions of the file, ...

1
2 3 4 5
57